Comparing methamphetamine, MDMA, cocaine, codeine and methadone use between the Auckland region and four Australian states using wastewater-based epidemiology (WBE)

To compare levels of drug use in Auckland with four Australian major cities using wastewater-based epidemiology (WBE).A week of daily wastewater samples were selected from two Auckland and eight Australian urban wastewater treatment plants (WWTPs) during 2014 and 2015. Samples were analysed for drug residues using liquid chromatography-tandem mass spectrometry. Consumption of methamphetamine, methylenedioxymethamphetamine (MDMA), cocaine, codeine and methadone (mg/day/1,000 people) was estimated for each WWTP from mass loads using an internationally validated back-calculation formula.Cocaine was not detected at either of the two Auckland WTTPs, and MDMA was detected on only one day of the sampled week in each of the Auckland WWTPs. In contrast, cocaine and MDMA was detected on every day at all eight Australian WWTPs. Methamphetamine was detected on every day at both the New Zealand and Australian WWTPs. Levels of methamphetamine consumption at the Auckland WWTPs were lower than five of the Australian WWTPs. Lower levels of codeine and methadone consumption were detected in Auckland than Australian sites.MDMA and cocaine use is low in Auckland compared to sampled Australia cities. Both Auckland and the selected Australian cities have significant methamphetamine problems compared to many European cities.